Fmoc-L-MeLys(N3)-OH is a click chemistry reagent featuring an azide functional group. This compound serves as an SPPS building block for the incorporation of N-Me-Lys, which can be modified through azide groups via click chemistry. Fmoc-L-MeLys(N3)-OH can undergo copper-catalyzed azide-alkyne cycloaddition reactions (CuAAc) with molecules that contain alkyne groups, and also participates in strain-promoted alkyne-azide cycloaddition reactions (SPAAC) with molecules having DBCO or BCN groups.